The present invention relates to systems and methods for computer integrated telephony and, more particularly, to systems and methods for integrating private branch exchange (hereinafter xe2x80x9cPBXxe2x80x9d) systems with local area network (hereinafter xe2x80x9cLANxe2x80x9d) servers.
The integration of telecommunication equipment with data processing equipment provides for powerful tools that coordinate the advanced features of digital telephony with the computer processing power of digital computer networks. For example, computer integrated telephony (CIT) systems exist that integrate PBX systems with LAN systems. These PBX CIT systems provide advanced call control and processing. For example, these CIT systems can run applications that detect incoming telephone calls, employ a caller ID function to determine the identified source of the incoming call, pass the source identification information to a computer database application program that employs the source identification as an entry point to the database. From the database, the CIT system can collect relevant customer records such as the invoice statements. The CIT system at that time can transfer both the incoming call and the associated data records to a customer service agent that is most suited for handling this incoming call. For example, if the invoice records show that the account associated with the call is overdue, the CIT system transfers both the incoming call and the relevant invoice data record to an available customer service agent in the billing department of the company.
The CIT systems that exist today include a PBX system that connects to a network server. The PBX system performs the telecommunication functions which include establishing circuit connections between calls from the public telephone system and the individual extension lines within an office. The server performs the data processing applications which can include maintaining databases and running client/server applications. The interface between the PBX and the server establishes a physical and logical connection between the server and the PBX that allows for the operation of CIT systems.
The physical connection between the PBX and the server is typically a conventional computer interface that includes an interface card located in the PBX, an interface card located in the server and a cable connection that extends between these two interface cards. The interface cards typically implement a conventional data communications protocol such as X.25 or ISDN. Through this channel, the PBX and the server can exchange data for coordinating the activities of these two systems during operation of CIT system applications.
The logical connection between the PBX and the server determines how messages are exchanged across the physical interface. Typically, a client/server application running on the computer network generates either requests for actions or requests for instructions for the PBX system. The client passes these requests on to the server. The server has a translator program that translates the message requests from the application program into commands that can be used to operate the PBX. These commands are sent to a software driver that puts the commands into a format suitable for transmission over the data channel, such as the ISDN line or X.25 line. The PBX system receives through its interface card the commands and performs the functions as dictated. The PBX then transmits status messages back to the server system which translates the PBX messages into a format that the application program can understand and the server sends the translated messages to the application program. The application program determines from the translated messages what data records the application program needs to access and proceeds to route the data records to the appropriate client computer and to send further instructions to the PBX system to route any associated incoming calls to the telephone associated with that client""s computer.
Although the above systems work to integrate data processing equipment with telecommunications equipment, the integration through the physical and logical connections is often perplexing and difficult to create and maintain. Firstly, most PBX architectures are proprietary, therefore the physical connection between the server and the PBX differs depending on the vendor. For example, an EtherNet port, such as the one found on the NEAX 2000 from Nec America, will be different from the ISDN BRI link employed by ATandT""s Definity system. Computer network managers that have to integrate the PBX system into the local area network often find the link between the server and PBX to be both cumbersome and unreliable.
Moreover, these present systems are dependent upon the proper operation of the network LAN server. In the event that the LAN server crashes, the CIT system application that operates the PBX system is brought down. Similarly, any time the computer network manager wishes to reinitialize the network server, those CIT applications that operate the telecommunication systems will also be brought down. Accordingly, the present systems are subject to failure and are difficult to maintain. A further difficulty exists, in that the development of CIT applications is made difficult by the proprietary PBX driver that translates messages from client/server applications into commands suitable for implementation by the PBX system. In particular, as each PBX driver is typically a proprietary software system, the development of standard applications is difficult, if not impossible.
Accordingly, it is an object of the present invention to provide CIT systems that provide an improved interface between telecommunication equipment and data processing systems.
It is a particular object of the present invention to provide a PBX system that more easily integrates with the server of a local area network.
It is a further object of the present invention to provide a LAN-integrated PBX system that has improved fault tolerance.
It is an additional object of the present invention to provide a CIT system that has greater performance and improved reliability.
These and other objects of the present invention shall be made more clear by the following description that references figures having reference numbers wherein like reference numbers refer to the same elements.
Computer integrated telecommunication systems are disclosed that provide an interface that transfers data and control requests generated by applications running on a computer system directly, and unchanged, to a telecommunications unit that is adapted to respond to the data and control requests generated by these application programs. In particular, PBX systems are disclosed that include calling interfaces that directly map telephony enabled application programs into the controller element of a PBX system. Further systems are disclosed that provide interfaces that allow the efficient transfer of audio signals between a computer system and a telecommunication unit and between a computer system of a first network and a computer system of a second network.
In one aspect, the invention is understood as systems that are adapted for being integrated into the server of a computer network. The systems include a carrier interface for coupling to a plurality of carrier lines suitable for transmitting signals to a telephone. The carrier interface can include a trunk interface for coupling to one or more trunk lines, or a subscriber loop interface for coupling to a plurality of extension lines wherein each extension line is of the type which is suitable for carrying signals to a telephone. In a preferred embodiment the carrier interface includes both a trunk interface and a subscriber loop interface. The system can further include a server interface having a bus port adapted for connecting to a bus slot of the server to form a data path with the server, a controller element that transfers message signals across the data path and that generates control signals responsive to the message signals, and a switch element that is connected into an electrical circuit with the controller elements and that establishes, in response to the control signals, circuits between the plural extension lines and the trunk lines. In this way, the system according to the invention includes an interface that directly maps telephony enabled application programs into the control program of a telecommunication system. This allows the telephony enabled application to have direct access and control over the integrated telecommunications equipment.
In a preferred embodiment of the invention, the controller element includes a processor element and a memory element that includes a calling interface element, typically a software program, that operates the processor element to generate the control signals in response to the message signals which are transferred unchanged across the data path to the server. The calling interface typically includes a switch element that responds to a message-type signal included in the message signal, and responsive to the message-type signal instructs the processor to generate the control signals. In a further preferred embodiment of the invention the calling interface element operates the controller element in response to message signals which are Computer Supported Telephony Application (CSTA) compliant message signals. The calling interface can further include an element for generating message signals for transfer to the server interface. Preferably the element for generating the message signals includes an element for generating CSTA compliant message signals.
In one embodiment of the invention, the calling interface element is a software program element that is preferably stored in read only memory element which is onboard a circuit card assembly that comprises a telecommunication system. In a further embodiment of the invention, the controller element also includes a memory element for storing a call control program element that implements the telecommunication functions of the system. Preferably the controller includes an onboard power supply element for supplying power to the controller element and the memory elements to thereby provide onboard call control independent of the functioning of the integrated computer system. Accordingly, telecommunication functions such as conference calling, call transfers, and call holding can be accomplished without support from the integrated computer equipment. This provides a system having improved fault tolerant operation.
The system further can include an exchange interface that couples to a second system according to the invention for exchanging message signals between plural, ones of these systems. Preferably the exchange interface comprises an Signal Computing System Architecture (SCSA) interface to allow the daisy chain interface of plural systems. In a further embodiment of the invention the system also includes an audio data transfer element that allows the transfer of data representative of audio signals to the integrated computer element, such as the file server.
In a further aspect, the invention can be understood as network server systems that include a message bus for carrying message signals, a server controller element for controlling the transfer of message signals across the message bus, a branch exchange element that includes a bus port connected to the message bus of the server to form a data path therewith, a trunk interface for coupling to a trunk line, a subscriber loop interface for coupling to a plurality of extension lines of the type suitable for carrying signals to a telephone, a controller element in electrical circuit with said bus port for transferring the message signals across the data path and for. generating control signals responsive to the message signals and a switch element that is an electrical circuit that is in electrical circuit with the controller element for establishing, in response to the control signals generated by the control element, circuits between the plural extension lines and the trunk line.
Network server systems according to the invention can also include control elements that have audio data transfer elements for transferring data representative of voice signals to the server controller element. The server controller element can also include a play audio element that has a data memory means for storing audio files of audio information and an audio file transfer element for transferring audio files to the branch exchange element. Moreover, the network server system can also include an internetwork interface element that allows for the transfer of audio files to a second network system.
In a further aspect, the invention can be understood as a telecommunication system that is adapted for. being integrated into a stand alone computer. The system includes a trunk interface for coupling to a trunk line, a subscriber loop interface for coupling to a plurality of extension lines of the type suitable for carrying signals to a telephone, a computer interface having a bus port adapted for connecting to a bus slot of the computer to form a data path with that computer, a controller element in electrical circuit with the bus port for transferring message signals across the data path and for generating control signals in response to the message signals and a switch element that establishes, in response to the control signals generated by the controller element, circuits between the plural extension lines and trunk lines.